Should I take precautions already?!?

my husband and I recently lost our baby and have decided to try again with no official timeframe yet. Well I just had my first postpartum period and of course he couldn’t wait for sex.

I noticed once we were done that he definitely left it in. He claims accident but I mean I’m upset or anything. But now here I am wondering my chances of already being pregnant again. Ive heard you’re extremely fertile in the first few months and I’d like to know if i should pause on drinking alcohol, eating medium rare food, etc until my next period comes or if I’m being too paranoid.